U.S. Pat. No. 5,662,187 provides means of delivering the torque from a rider's pedalling and the torque from an electric motor to a fixed diameter freewheel as a blend, simultaneously.
There is no provision for taking advantage, on the riders part, of the build-up of momentum, that could be used to improve propulsion efficiency by providing a means that would allow selective use of variable points of leverage, along a freewheel radian, while applying pedal torque to the freewheel.